Thank you for the kind words! I would love to see the VOD once you have it, 10 minutes is pretty quick relative to my other playtesters, you must've taken to the game pretty well, that makes me happy :)
We will probably add an angle guide in an update, enough people have asked for that so I clearly underestimated the qol benefit of it, oops.
Having hold to swim on a different button sounds pretty reasonable too, I'm kicking myself for not thinking of that on my own. But I probably won't sit down to figure that one out until we have more levels to play in. Expanded underwater sections are on the drawing board anyways, so it'd go right along with that.
As for the window being cut off... I'm honestly not entirely sure what you mean by "cut off", but I guess I can't reproduce that one since it looks normal to me. Might be desktop resolution specific? The window is resizable, but the game is locked to 16:9 ratio, so for example if you have a 16:10 monitor it would add black bars to the top and bottom if that's what you mean. Oh and Alt+Enter should work to fullscreen the game, I don't advertise it because that also hides the all important close button and I haven't added an in game quit button yet, but it's a fairly common key combo regardless.
Edit: Oh... I think I get it, you have a 1080p monitor, the game loads in a 1080p window, but the OS prefers to nudge the title bar into view, so the whole game gets shifted down by a few pixels on load. Yeah... the maximize button should fix that too, but I'll think about a way to make that better, probably just a godot configuration option I can set somewhere.